The invention relates to a corrective insole for treating defective positioning in the metatarsal and forefoot areas of the foot.
Such defective positioning, such as hallux valgus, hammer toes, or claw toes, sometimes occurs due to hereditary abnormalities and sometimes due to faulty footwear or overloading or malpositioning of the lower extremities. The following explanations are limited relate to widespread malpositioning known as hallux valgus, and are also applicable to other types of defective positioning in the metatarsal and forefoot area. Hallux valgus is defined as an outward deviation of the big toe at the metatarso-phalangeal joint. The term, “outward” here and in the following always indicates a direction away from the center plane of the body; specifically towards the small toe. Consequently, the term, “inward” is in the opposite direction, that is, from the small toe towards the big toe. In hallux valgus, the tendons of the toes no longer run centrally across the joint, but rather run further inward, and they pull the toes into a slanted position relative to each other. The ball of the big toe, which projects because of this slanted positioning, frequently suffers painful inflammation, caused by the pressure of the shoe in this area. At the same time, the angle between the various metatarsal bones is enlarged, especially between the metatarsal bone adjacent to the big toe and the proximal phalanx of the big toe. A frequent accompanying symptom is arthrosis. Among the causes of hallux valgus are splay foot, with the anterior transversal arch caving in and the big toe deviating as a result, and especially faulty footwear, which, due to fashion, is frequently worn in a size that is too small, has heels that are too high, or has a toe area that is too narrow.
In addition to surgical treatment, orthopedic measures such as special splints or corrective insoles are customary for correcting hallux valgus.
One such corrective insole is known from DE 20 2004 006 113 U1. This publication describes an insole that in the toe area has an elastic strap that is guided through a slit in the sole. This strap can be stretched about the big toe such that it brings it into a position required for correcting hallux valgus.
The aforementioned insole it is disadvantageous since it only corrects defective positioning of the big toe itself. This is not sufficient for effective and lasting correction of defective positioning described above since there is no change in the angular position of all the metatarsal bones.
Thus, it is desired to provide a corrective insole that attains improved and comprehensive correction of defective positioning of all of the foot bones with respect to the conditions described.